Typewriting machine



Oc't. 29, 1940. H. n.. PITMAN TYPEWRITING MACHINE Filed May `10, 1958 2 Sheets-Sheet 1 HENRY L. PITMAN,

ATTO R N EY oct. 29, 1940. 4 H, L, MAN 2,219,371

TYPEwnITmG MACHINE Filed May 1o, 193s V2 sheets-sheet 2 INVENTOR RY L.P-|TMAN,

Patented Oct. 29, 1940 UNITED STATES PATENT OFFICE TYPEWRITIN G MACHINE Henry L. Pitman, Hartford, Conn., assignor to Underwood Elliott Fisher Company, New York, N. Y., a corporation of Delaware Application May 10, 1938, Serial No. 207,062

5 Claims.

nitely controlling the tendency of the carriage to rebound at said impact.

An object of the invention is to provide improved impning and rebound-controlling devices that are reliable in operation and are constructed of simple parts that may be ap` plied economically to typing machines.

There is employed a tabulating-stop rack structure that is removably attached to the carriage by an easily interlockable and separable connection so that a setting of tabulating stops carried by the rack may be removed, along with the rack, from the machine for replacement by another rack carrying a different setting of stops.

A further object of the invention is'to dispose a cushioning and rebound-controlling device between the stop-carrying rack and the carriage, and to adapt such device so as to freely permit removal and replacement of the rack.

A feature of the invention is in adapting the aforementioned easily interlockable and separable connection between the carriage and rack so as to permit movement of the carriage in tabulating direction upon arrest of the rack by a counter-stop and to check this movement by a resilient cushion such as a spring, whereby to cushion the impact.

At the impact of the rack with a counter-stop, the spring may yield inasmuch as it absorbs the impact shock by permitting the 'carriage to move independently in tabulating direction relatively to the arrested rack. The spring then recovers, thereby moving the carriage back relatively to the arrested rack.

A further feature ofthe invention resides in definitely braking the backward or recovery movement of the carriage relatively to the rack so as to minimize the momentum of said backward movement and thereby counteract recoil of both the carriage and rack from the counterstop. The braking may be effected denitely by means of a friction connection, and a. further feature of the invention is in means adapted for regulating the braking eiect.

The definite braking or friction connection may be arranged so as to be eiiective also during the impact-absorbing movement of the carriage relatively to the rack in tabulating direction, said friction connection thereby cooperating with the cushioning spring to cushion the impact.

In a typewriting machine such as the Underwood, the carriage runs upon front and rear rails mounted on the machine frame. The front rail 5 may be of channel section presenting upper and lower flanges. It is a further feature of the present improvements to provide, instead of the usual rollers spaced at intervals on and along the front cross-bar of the carriage-frame to bear on said iianges, a continuous rail or bar on said front carriage-frame bar adapted to t slidably against said front rail flanges. Said bar may be 4co-extensive substantially with the length of the carriage-frame and may be attached to said 1 iront carriage-frame cross-bar so as to reinforce the latter while, at the same time, serving, as a part presented by the carriage, to engage said rail anges. The continuous bar, slidably engaging the front rail, also serves to keep the carriage steady in its travel and thereby conduces to evenness of the typing.

'Other features and advantages will hereinafter appear.

In the accompanying drawings:

25 Figure 1 is a rear view section on the trace I--|, Figures 4 and '7, showing details of the carriage-impact-cushioning and rebound-controlling devices.

Figure 2 is a plan-view diagram of the car- 30 rage, carriage-feeding mechanism and the machine frame.

Figure 3 is a perspective of portions of the carriage tabulating mechanism and said impactcushioning and rebound-controlling devices.

Figure 4 is a top plan View showing the left side portion of the tabulating rack as attached to the carriage, and the cushioning and reboundcontrolling devices.

Figure 5 is a perspective showing the tabulating rack detached from the rack-mounting part of the carriage and showing said part mounting, the impact-cushioning and rebound-controlling device.

Figure 6 is a cross-section View at the middle of the interlocked tabulating rack and said rackmounting part.

Figure 7 is a top plan view, showing the right side portion of the tabulating rack and its attachment to the carriage.

A typing carriage C, Figures 2 and 3, comprises a frame I5 adapted to travel on iront and rear rails I6, I1 mounted on a typewriter frame Il.

At operation of type keys I4 to drive types 29 5 to a platen 2| mounted in said carriage C, the usual escapement mechanism, represented by escapement wheel 22, Figure 2, is actuated for resulting letter-feed of the carriage by a spring motor 24 connected to the carriage by a drawband 25. The escapement mechanism includes the usual type-key-controlled dog-device (not shown), normally restraining the escapement wheel 22 and carriage C, the carriage mounting a letter-feed rack 26 engaging a pinion 21 coupled to the escapement wheel 22.

A carriage tabulating mechanism may include a series of denominational counter-stops 29 in the form of reeds, Figure 3, assembled in a housing 30 on the frame I8, said reeds being adapted to be elevated selectively, by means of denominational tabulating key-levers 3| to bring their upper ends into the path of column stops 32 settable in a rack structure 33 removably attached to the carriage, as will presently be described. At elevation `of any one of the denominational counter-stops 29, an arm 34 thereof displaces a universal bar 35 xed to a rock-shaft 36 journaled in the housing 30 to rock said shaft counter-clockwise of Figure 3. Said rock-shaft 36, when thus rocked, acts through the usual connection represented diagrammatically by the dot-and-dash line 39, Figure 2, to lift the letterfeed rack 26 from the escapement pinion 21, thereby releasing the carriage for a resulting tabulating jump to the left, the jump being arrested when the column stop 32 on the carriage is intercepted by the elevated counter-stop 29. At release of the operated denominational tabulating-key lever 3|, the elevated counter-stop 29 is retracted by its individual spring 40, Figure 2, and concomitantly, the universal bar 35 and its rockshaft 36 are caused to be restored so that the letter-feed rack reengages the escapement pinion 21 in the usual manner to settle the carriage at the tabulated-to position. The tabulating key and counter-stop mechanism and associated carriage-releasing means are not described in further detail herein since such detail is exemplified in Patent No. 1,858,447 to W. F. Helmond, dated May 17, 1932.

The open carriage frame includes side members 4| and front and rear cross-bars 42, 43, joining said side members. The rear cross-bar 43 has fixed thereto, by screws 44, side brackets 45, each presenting an upright wall 46. A bracket-spanning angle bar 41 has one leg 48 xed vertically to the bracket Walls 46 by screws 49, Figures 3 and 5. A horizontal leg 58 of said angle bar 41 has at its left end a notch or slot adapted to receive slidably by Way of the open left end of the slot, Figure 5, a reduced neck formed on a rack-structure stud 52 by a groove 53. The groove 53 is slightly wider than the thickness of the slotted part of the angle bar so that an upper stud-flange 54, formed by said groove may rest slidably on the upper face of the horizontal anglebar leg 50. The rack-structure stud 52 is entered rst into the angle-bar slot 5| after which the rack-structure 33 is swung clockwise of Figures 4, 5 and 1 from a cocked stud-introducing position to enter another rack-structure stud 56, grooved similarly to the stud 52, into a notch or slot 51 at the right end of angle bar 41, said slot 51 opening at the rear edge of said angle bar. The rack-structure 33 includes a front rack 58 surmounted by the studs 52, 56. Fixed to the ends of said rack 58 and extending rearwardly therefrom are arms 60 presenting upturned ears 6| which mount a rear rack 59 having letter spaced notches 62, Figure 6, on its under side similar to letter spaced notches 63 of the front rack 58.

With the rack-structure studs 52, 56 entered into their respective notches 5| and 51, as in Figures 4 and 5, a latch hook 64 may engage the front of a stud 65, Figure 7, projecting upwardly from the angle-bar 41 to releasably keep the rackstructure 33 in place. The right-hand notch or slot 51 has a left edge which normally abuts the reduced neck of the right stud 56 as at 61, Figure 7, to stop leftward displacement of the rackstructure on the carriage. The latch hook 64 is formed on a. plate 68 pivoted to the rack-structure, as at 69, Figures 3 and 7. A spring 1| yieldably holds the latch-hook plate 68 in rack-structure-latching position. A ringer piece 12 on said latch-hook plate serves for swinging the plate counter-clockwise of Figure 7 to withdraw the latch hook 64 from the stud 65 preparatory to withdrawing the right-rack-structure stud 56 rearwardly from its companion angle-bar slot 51; the rack structure being then completely detachable from the carriage by moving it leftward out of the left slot 5I.

Each column stop 32 may be formed on a unit 14 having front and rear teeth 15 and 16 for articulation with the notches 63, 62 of the front and rear racks 58, 59; and each unit 14 further has ears 11 adapted to hook over the top of the rear rack 59. Each unit 14 is withdrawable endwise from the racks 58, 59 and is placeable at any one of the letter-spaced rack stations afforded by the rack notches. A stop-placing scale 18 is xed to the rack structure, as at 19, Figures 3 and 6. Each unit 14 has a detent spring 80 adapted to clip into a groove 8| of the front rack 58 to keep the unit in place.

Fingers 82 project rearwardly to underlie the rack-structure arms 6l) to support the latter, as at 83, Figure 3, to keep the rack-structure 33 from sagging about its loose connections to the angle bar 41 at the studs 52, 56. Said ngers 82 have upturned forward ends 84 rigidly xed to the carriage by the screws 49 that secure the angle bar 41 to the carriage bracket walls 46.

A double-angle bar 85 has a horizontal leg 86, Figures 1 and 6, immovably xed to the top of the angle bar 41 as by spot-welding or riveting; and a forwardly projecting leg or flange of said double angle bar forms a cross rail 81 engageable with a stationary guide (not shown) to cooperate to support the weight of the parts that are carried by the brackets 45.

The rack structure 33 and the easily interlockable and separable connection for removably attaching it to the carriage are, as so far described, substantially along the lines disclosed in my co-pending application Serial No. 72,348, filed April 2, 1936.

The devices for cushioning the impacts of the column stops 32 with the counter-stops 29 at thev arrests of tabulating jumps of the carriage and for controlling rebound of the carriage, will now be described.

Upon the carriage proper and, therefore, overlying the horizontal leg 86 of the double-angle bar 85 is a bar 96 having longitudinal slots 9|, 92, Figures 1 and 4. A stud 93, riveted into the horizontal legs 50, 86 of the angle-bars 41, 85, as at 94, Figure l, projects through the slot 9| of said bar 90. Another stud 95, riveted into said horizontal angle-bar legs, as at 96, is received in the slot 92 of said bar 98 and has a head 91 between which and the horizontal leg 86 the bar Cil 90 is slidably retained. Said stud 95 has an upward extension 98 between which and a stud 99, riveted into the bar 90, as at |00, a spring |I is stretched. Said spring IOI thus holds said bar 90 with one end of either or both of its slots 9|, 92 in abutment with the respective studs 93, 95, as in Figure 1. The bar 90 has an end |03 adapted so that when the rack structure 33 is in place it abuts the side of said stud ange 54, as at |04, Figure l.

It will be perceived now, referring to the rear elevation, Figure 1, in which the carriage-tabulating movement is to the right, that at the interception of a column stop 32 on the rack structure 33 by the counterstop 29, the rack structure, including the stud 52, is arrested; and, since the stud flange 54 abuts the end of the slide bar 90 on the carriage, said slide bar is also arrested. But the slots 9I, 92 in said bar 90 leave the carriage proper, together with its angle bars 41, 85, free to move independently by momentum relatively to said thus arrested bar 90 and rack structure 33. To permit such independent movement of the carriage, the slots 51 of the angle bar 41 are elongated to the right of their respective studs 52, 56 as in Figures 4 and '1. It will be perceived that the rack structure retaining latchhook 64 is also adapted to permit such independent carriage-movement. The spring IOI yields with said independent movement of the carriage proper relatively to the arrested bar 90. The spring IOI is strong enough to yield or stretch only limitedly whereby to resiliently overcome and check said movement and thereby absorb and cushion the impact of the carriage-arrest.

After checking said independent movement of the carriage, the stretched spring IOI resiliently recovers and thereby effects a reverse movement of the carriage and its angle bars 41, 85 relatively to the arrested rack-structure 33 and slide bar 90.

The following devices brake, and therefore retard said reverse movement so that its momentum is minimized by the time the studs 93, 95 again abut the ends of their respective slots 9|., 92, as in Figure l, and, therefore, tendency of the carriage, together with the rack-structure, to rebound or recoil from the counterstop 29, is minimized.

The stud 93 projects through a slot |06, Figure 1, in a plate |01 which loosely overlies and is movable with the slide bar 90 relatively to the angle bars 41, 85 in that the spring stud 99 of said slide bar 90 closely ts a hole in said plate |01. The stud 93 has an upwardly extending screw |08 passing through ,a leaf-spring |09 adapted to press upon the plate |01 when said spring |09 is held under strain by means of a washer IIO and a nut I|I- threaded upon said screw |08.

The plate |01, thus pressed by the spring |09, in turn presses upon the slide bar 90 so that the latter presses upon the leg 86 of the underlying angle bar 85. The leaf spring |09 thus imposes a frictional braking effect, at the contacting sur faces of said slide bar 90 and the angle-bar leg 86 and also at the contacting parts of the plate |01 and the spring |09, which retards relative movement of said bar 90, and the carriage with its angle bars 41, 85. The frictional braking effect thus minimizes the momentum of the reverse carriage movement that occurs when the spring |0I recovers resiliently after its impactabsorbing stretch, and', therefore, liability of rebound or recoil of the carriage from the counterstop 29 is minimized and proper reengagement of the letter feed rack 26 and pinion 21 is insured. The frictional braking effect may be immediately effective at the start of said reverse carriage movement. The braking pressure of the leaf spring |09 may be regulated by adjusting the nut I-II up or down upon the screw |08 and the adjustment may be held by means of a check nut II2. The frictional braking eect also obtains when the carriage moves independently in tabulating direction following arrest of the rack structure 33, and is thus cooperative with the spring |09 in cushioning the impact so that said spring does not have to yield excessively. It will be understood, of course, that the spring IOI is made strong enough to overbalance the frictional braking eiect of the spring |09.

Referring now to improved means whereby the carriage is guided in its travel by the front rail I6: Said front rail I6 is of channeled cross-section, Figure 3, presenting upper and lower flanges II4. To the front cross-bar carriage frame I5, and substantially coextensive therewith, Figure 2, is attached a bar |I5 of a height to t slidably and substantially without up-and-down play between said upper and lower rail flanges II4. Said bar |I5 may be attached, as by screws IIB, to bosses I I 1 provided in suitable number upon and extending forwardly from the vertical leg of said carriage-frame cross-bar 42, the latter being, in the present machine, of angular cross-section. It is found that such bar I|5 slides very freely and therefore with negligible friction between said upper and lower rail flanges I I4 and requires very little lubrication. The carriage frame I5 may have the usual Underwood collars or lugs II8 adapted to embrace the round rear rail I1 and to slide along the latter. Such rear-rail contact of the carriage holds the latter against fore and aft play so that the front face of the front bar I I5 need not contact the front rail I6.

Said bar II5 is an inexpensive medium of contact of the carriage with the front rail as compared with the usual ball-bearing-mounted or large diameter rollers heretofore employed. Moreover, said bar I I5 reinforces the carriageframe bar 42 structurally so that liability of strain or breakage of the carriage frame is avoided, such breakage or strain otherwise being liable to occur as when it is attempted to lift the machine by taking hold of the carriage when the latter projects laterally beyond the front rail` I6, as in Figure 2. The front bar I I5 always affords a large spread of contact with the front rail I6 to keep the carriage from teetering in its letter-feeding movements, thereby conducing to evenness of the typing. The upper and lower surfaces of the bar I I5 may be provided with notches I9 adapted to prevent accumulation of dust or dirt between the sliding surfaces.

'Ihe column-stop including units 14 for which the rack structure 33 is devised, may have tappets (not particularly shown herein) adapted to actuate denominational elements of computing mechanism that may be combined with the typewriter mechanism as set forth in my aforesaid application No. 72,348. In order to support the rack 58 against flexure, said rack may have on its front face a groove adapted to fit slidably a racksupporting vstud |2I, Figure 6, secured to the vertical leg of the angle bar 41 as by a screw |22. The top of the rack may have studs |23 adapted to bear on the under side of the horizontal leg 50 ofsaid angle bar 41 and'thereby cooperate to support the rack 58 against exure.

What is claimed as new is:

1. The combination with a power-urged typing carriage, or the like, releasable to jump to a counter-stop, of a rack on the carriage mounting a stop cooperative with said counter-stop, said rack having studs and the carriage having slots to receive said studs whereby the carriage may move in jumping direction relatively to the rack at the impact of the rack-carried stop with said counter-stop, a bar movably mounted on the carriage and engaging one of the rack studs so that said carriage is movable relatively to said bar at said impact, an impact-cushioning spring connecting said bar and carriage and yielding as the carriage moves relatively to said rack at said impact, and means connecting said bar frictionally to said carriage to resist frictionally and thereby retard the reverse movement of said carriage occurring as the cushioning spring recovers and moves the carriage reversely relatively to said rack and bar.

2. The combination with a power-urged typing carriage, or the like, releasable to jump to a counterstop, of a rack on the carriage mounting a stop cooperative with said counter-stop, said rack having studs and the carriage having slots to receive said studs whereby the carriage may move in jumping direction relatively to the rack at the impact of the rack-carried stop with said counter-stop, a bar movably mounted on the carriage and engaging one of the rack-studs so that said carriage is movably relatively to said bar at said impact, an impact-cushioning spring con necting`said baand'arriage 'and'yielding as the carriage moves relatively to said rack at said impact, and a spring pressing said bar on said carriage to cause frictional retardation of the reverse shift of said carriage occurring as the cushioning spring recovers and moves the carriage reversely relatively to said rack and bar.

3. The combination with a tabulating carriage, of a stop-rack, supporting means on the carriage for receiving the rack at its end portions detachably to permit ready removal and replace- 45 ment of the rack at will by manipulation, said supporting means constructed to permit longitudinal movement of the carriage relatively to amw the rack at impact of a stop on said rack with a counterstop, and a cushioning device permanently mounted on the carriage and operatively connected to said rack to react to said longitudinal movement of the carriage to cushion said impact, said cushioning device and its operative connection to said rack being arranged to permit freely said ready removal and replacement of the rack.

4. The combination with a tabulating carriage, of a stop-rack, a part permanently mounted on and movable longitudinally of the carriage, means for connecting said rack at its end portions to said carriage detachably so as to permit ready removal and replacement of the rack at will by manipulation, said connection means constructed to permit longitudinal movement of the carriage relatively to the rack at impact of a stop on said rack with a counter-stop, and a spring cooperative with said part to react to said longitudinal movement of the carriage to cushion said impact, said rack, by being in place on the carriage, having operative connection to said part so that said carriage also moves longitudinally relatively to said part, against the urge of said spring, at said impact.

5. The combination with a tabulating carriage, of a stop-rack, a part permanently mounted on and movable longitudinally of the carriage, means for connecting said rack at its end portions to said carriage detachably so as to permit ready removal and replacement of the rack at will by manipulation, said connection means constructed to permit longitudinal movement of the carriage relatively to the rack at impact of a stop on said rack with a counter-stop, a spring cooperative with said part to react to said longitudinal movement of the carriage to cushion said impact, said rack, by being in place on the carriage, having operative connection to said part so that said carriage also moves longitudinally relatively to said part, against the urge of said spring, at said impact, and a frictional connection between said part and carriage acting to retard the springurged rebound or recovery movement of said carriage relatively to said rack and part.

HENRY L. PITMAN. 

